Herein, “goods” is a generic label for content which is represented on/by a physical medium or on/by an electronic medium. Examples of physical medium representation include printed image and printed document or other data. Examples of electronic medium representation include electronically stored or transmitted images, audio clips, video, multimedia, software, and data.
There are many conventional approaches designed to aid in goods authentication and/or deter counterfeiting. Sophisticated document production is the most common approach.
Counterfeits
For as long as important documents (which are examples of “goods”) have existed, ne'er-do-wells have forged them when they could not acquire, would not acquire, or could not afford to acquire the real thing.
Counterfeit money was often the product of their forgery. To combat and deter such counterfeiting (of money or other important documents), issuing organizations have produced documents with increasingly more sophistication.
Sophisticated Production
The test of the veracity of important documents has been the difficulty of producing such documents. Often important documents have counterfeit-deterrence features. For example, the receiver of legal tender assumes that it is authentic because of the great difficulty and sophistication required to produce a passable counterfeit.
However, recent advances in printing technology have made high-quality printing devices relatively inexpensive. Furthermore, recent advances in imaging technology have made high-quality image manipulation software relatively inexpensive and readily accessible.
The availability of high-end printers and advanced imaging software has rendered forging most goods (such as important documents) a relatively simple task. In response, issuing organizations (such as governments) have implemented increasingly more sophisticated and presumptively more expensive production techniques. Examples of such sophisticated production techniques include employing one or more of the following in the final goods: holograms, watermarks, micro-printing, special print paper, security threads, magnetic properties, and chemical flags.
Watermarks
Historically, a traditional watermark is a faintly visible mark imprinted on or embedded in print media (such as stationary) that typically identifies the source of the print medium. Watermarks have been around almost as long as print media (such as paper) as existed. Like hallmarks on silver, watermarks were originally used to show which artisan had produced which paper. They later became synonymous with security, appearing on banknotes to deter counterfeiters. Herein, this type of watermark is called a “traditional watermark.”
Like a traditional watermark, a “digital watermark” is an embedded identifying mark, but it is embedded into digital goods. It typically contains hidden identification data and is often used to track the use of copyrighted materials.
Unlike traditional watermarks, which are intended to be somewhat visible, digital watermarks are typically designed to be completely imperceptible to the human senses. If it is an image, then the digital watermark is typically invisible to the naked eye. If it an audio clip, then the digital watermark is typically inaudible to the human ear. While it is imperceptible to humans, digital watermarks are typically at least detectable by a specifically designed digital watermark detector.
Those of ordinary skill in the art are familiar with conventional techniques and technology associated with watermarks, watermark embedding, and watermark detecting.